@@ 493,27 493,30 @@ be read."
(define (machine-load machine)
"Return the load of MACHINE, divided by the number of parallel builds
-allowed on MACHINE."
+allowed on MACHINE. Return +∞ if MACHINE is unreachable."
;; Note: This procedure is costly since it creates a new SSH session.
- (let* ((session (open-ssh-session machine))
- (pipe (open-remote-pipe* session OPEN_READ
+ (match (false-if-exception (open-ssh-session machine))
+ ((? session? session)
+ (let* ((pipe (open-remote-pipe* session OPEN_READ
"cat" "/proc/loadavg"))
- (line (read-line pipe)))
- (close-port pipe)
-
- (if (eof-object? line)
- +inf.0 ;MACHINE does not respond, so assume it is infinitely loaded
- (match (string-tokenize line)
- ((one five fifteen . _)
- (let* ((raw (string->number five))
- (jobs (build-machine-parallel-builds machine))
- (normalized (/ raw jobs)))
- (format (current-error-port) "load on machine '~a' is ~s\
+ (line (read-line pipe)))
+ (close-port pipe)
+
+ (if (eof-object? line)
+ +inf.0 ;MACHINE does not respond, so assume it is infinitely loaded
+ (match (string-tokenize line)
+ ((one five fifteen . _)
+ (let* ((raw (string->number five))
+ (jobs (build-machine-parallel-builds machine))
+ (normalized (/ raw jobs)))
+ (format (current-error-port) "load on machine '~a' is ~s\
(normalized: ~s)~%"
- (build-machine-name machine) raw normalized)
- normalized))
- (_
- +inf.0))))) ;something's fishy about MACHINE, so avoid it
+ (build-machine-name machine) raw normalized)
+ normalized))
+ (_
+ +inf.0))))) ;something's fishy about MACHINE, so avoid it
+ (_
+ +inf.0))) ;failed to connect to MACHINE, so avoid it
(define (machine-lock-file machine hint)
"Return the name of MACHINE's lock file for HINT."